The early users being patent secretaries, then "administrative kind of stuff, typing in trouble tickets," and adoption spreading because people liked it, is kind of cool. That creates different kinds of pressures than a big top-down-dictated project does, maybe healthy pressures: if you're going to play with a new idea about how things should work you can't break things; you need the thing running reliably for the people using it day-to-day. One way you can have huge projects fail is by fiddling around too long without contact with reality.
Given Linux's origins--"(just a hobby, won't be big and professional like gnu)"--it's interesting that early UNIX, in this telling, was also not the big professional push to build the OS of the future so much as just some folks trying to cobble something useful together (though of course, that they were playing around in Bell Labs gave their experiment some great advantages!).